Just as an interesting sidelight, I received notice today that 400 people were sickened by noro virus in a water park in New York State, and that an all-inclusive resort in Jamaica was closed because of a noro outbreak.

Noro isn't just a cruise ship problem, although cruise ships are the only venue obligated by law to report outbreaks. They are common to schools, nursing homes, jails, hotels, and resorts, among many other places.